Radiation sensitive apparatus for verifying label position



July7,1'970. J,R, AV.E'S 3,519,835

RADIATION SENSITIVE APPARATUS FORVERIFYING LABEL POSITION Filed June 5, 1968 2 sheets sheet 1 A A A IN TOR.

July 7, 1970' J. R. DAVIES 3,

RADIATION SENSITIVE APPARATUS FOR VERIFYING LABEL POSITION Filed June 5, 1968 2 Sheets-Sheet 2 CAN SWITCH SWITCHED H euse? CELLS SIGNAL COMPARATOR INVENTOR. 4/0 2. 041/153 92 9 on MACHINE United States Patent 3,519,835 RADIATION SENSITIVE APPARATUS FOR VERIFYING LABEL POSITION John R. Davies, Grand Rapids, Mich., assignor to Oliver Machinery Company, Grand Rapids, Mich., a corporation of Michigan Filed June 3, 1968, Ser. No. 734,040 Int. Cl. G06]; /04

US. Cl. 250-223 7 Claims ABSTRACT OF THE DISCLOSURE Apparatus for verifying the accuracy of label position on articles periodically advanced, using spaced indicia printed on the label in combination with photoelectric sensing units specially mounted to scan the indicia area of the label until the sensed indicia create an output sensing signal of a predetermined amount, and then locking in the sensing elements to take a comparative reading on the spaced indicia.

'RELATED APPLICATIONS This application is related to copending applications Ser. No. 500,047, filed Oct. 21, 1965, entitled Labeling Machine now US. Pat. 3,451,874 and Ser. No. 692,104, filed Dec. 20, 1967, entitled Labeling Machine.

BACKGROUND OF THE INVENTION This invention relates to article labeling and verification apparatus, and more particularly to apparatus for verifying the accuracy of labels on containers or like articles, and having a special scanning system.

In recent years, machines have been developed at Oliver Machinery Company, the assignee herein, capable of separating labels from a tape and applying them to indivdiual containers very accurately and at high rates. These have been eagerly accepted, even by the pharmaceutical trade which is particularly concerned with accuracy of labeling and which often utilize small containers. Such machines are fully described in copending patent applications Ser. No. 500,047, and Ser. No. 692,104.

Labels for such uses are accurately printed on a label tape, include printed information, and include a system of accurately printed code indicia for product verification expiration date verification, and label position verification. The labels are accurately severed from the tape and applied to the articles with extreme exactness. These operations are controlled within thousandths of an inch. With these machines, the labels can actually be verified after they are applied to the containers. The machines exactly grip and advance the labeled articles to the verification station.

Experience with these machines has shown that, in spite of these accurate operations, difficulties can occur in verification of the labels on the articles with highly sensitive photoelectric sensors. It has been determined that this occurs because of the significant variation in diameter of the containers on which the labels are applied. This variation from container to container causes the label indicia to fall outside the scope of the sensors too frequently.

SUMMARY OF THE INVENTION It is an object of this invention to provide labeled article handling and verifying apparatus capable of dependably verifying labels on articles, particularly containers, even though such containers vary in diameter. The equipment first specially scans each label on an article in the verification station, to locate the verification indicia, and then tests the indicia photoelectrically for verification pur- "ice poses. These operations are automatically sequentially performed after each labeled article is positioned by the article retainer advancer to be verified. The photoelectric sensing means scans the indicia area of the label until its output signal reaches a predetermined value due to the detection of at least a minimum amount of the spaced printed indicia on the label, and then for evaluating the askew orientation of the label on the container, compares the relative signals from the spaced indicia.

These and other objects of this invention, and the details of its construction and operation will be understood from a study of the following specification taken in conjunction with the drawings.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a perspective fragmentary view of the front of the novel apparatus;

FIG. 2 is an enlarged fragmentary perspective view of a portion of the apparatus in FIG. 1;

FIG. 3 is a schematic block diagram of the circuitry of the apparatus;

FIG. 4 is an enlarged elevational view of one container with a label applied thereto;

FIG. 5A is a fragmentary enlarged elevational view of a portion of the label in FIG. 4 during the first stage of the operation, i.e. scanning; and

FIG. 5B is a view like 5A showing the second stage of the operation i.e. verification.

DESCRIPTION OF THE PREFERRED EMBODIMENT Referring now specifically to the drawings, the complete apparatus 10 there shown basically includes a machine capable of feeding a label tape, severing the tape into individual discrete labels, advancing the separated labels to the label application station (advancing the articles to the label application station), applying the individual labels to articles, and advancing the labeled articles successively to the verification station where the verifying means of the combination becomes effective. Since the basic label tape advancement, severing, and feed mechanism is taught in copending application Ser. No. 692,- 104, referred to above, and since the basic article gripping, advancing, and retaining assembly are also taught in said application, the details of some of these components will not be reiterated here.

Basically therefor, the components of assembly 10 illustrated in FIG. 1 include subassembly 12 for advancing the labels, subassembly 14 for applying the labels to articles, subassembly 16 for advancing the articles to the labeling station and then advancing them further to the verification station, and subassembly 18 forming the verifying mechanism.

Article advancing subassembly 16 is basically a rotational wheel mounted on central axis 22, and normally composed of a pair of spaced parallel discs 24 and 24' held in constant relation with respect to each other, and including around the periphery thereof a plurality of container gripping means, each formed a fixed stop 26 on disc 24, and a spring biased axially shiftable gripping plunger means on disc 24. This gripping means includes a plunger 28 extending through a peripheral portion of disc 24, having an enlarged outer head 30 for retracting the plunger when the bottle is to be inserted or released, enlarged inner head 36 for engaging the bottle container, a compression spring 32 extending between disc 24 (and specifically insert 34 thereof) and enlarged inner head 36. Thus, each individual bottle or other container or like article is gripped at its ends, to allow its periphery to be exposed. As noted, the wheel means is capable of gripping a plurality of such bottles around its periphery, with the bottles normally being received at the nine oclock position (as viewed in FIG. 1), labeled in thetwelve oclock position, verified in the one thirty oclock position, and discharged after verification, between the three oclock and six oclock positions as desired.

The specific mechanisms and controls of the receiving, clamping, releasing, and drive mechanism for subassembly 16 are illustrated in copending application Ser. No. 692,- 104. Basically, the wheel means revolves one step at a time, with each clamping means, and each retainedbottle being advanced through a fraction of a revolution during each wheel intermittent movement. Here the fraction is one eighth due to eight stations being present on'this' particular wheel means. This could be varied as desired.

When in the twelve oclock position, the bottle is labeled bysubassembly 14, with central element 40 thereof being vertically reciprocable to hold a label L on a bottle B, after which wiper arms 42 and 42 straddling holder 40 vertically reciprocate to wipe the label down along the sides of the bottle periphery. Each bottle is then held in fixed relationship axially and rotationally with respect to the wheel as the wheel means advances to the verification station which, in the illustrated form of the invention is the first station after the label application station.

At this verification station, a light source such as the fiber optic light source 50 projects light upon the label, and specifically upon the leading edge of the label which contains the verification indicia illustrated most clearly in FIG. 4. This verification indicia can serve a multiple of verification functions as explained in detail in the above identified copending application Ser. No. 692,104, specifically code (for product) verification, imprinter (for expiration date) verification, and label position verification. The small indicia circles 60 in FIG. 4 illustrate one example of the typical binary code indicia system used for product verification. The large square spaced indicia 62 and 62' serve for label position verification. Photoelectric sensor subassembly 18 cooperates with these indicia for verification purposes. This same subassembly 18 may be employed for all noted verification. The primary verification used to explain this invention is the label position verification. Further, in order to simplify the explanation sufficiently to enable the system and apparatus to be readily understood, the skew position verification will be largely described. It will be realized that the photoelectric means is capable also of verifying the lateral and longitudinal positions of the label.

As noted previously, the label verification and orientation checking subassembly 18 is oriented toward the labeled bottle in the verification station which is the first one past the labeling station. This subassembly basically has a photoelectric sensor means 60 including a suitable lens or lenses in cylindrical scope housing 62, which project the code indicia back to a receiver 64 which has a series of photoelectric sensors correlative to the spaced code indicia on the label. These sensors each respond to the amount of light reflected from the portion of the label which they view and emit an electrical signal of corresponding value. In order to limit the area viewed by each sensor, a plurality of masks (illustrated for example by the phantom lines in FIG. 5A and SE at 72 and 72), are aligned with the respective indicia marks 62 and 62' on the label L. These masked openings 72 and 72' may be rectangular in configuration as illustrated, or may be of some other configuration such as triangular as explained in cop-ending application Ser. No. 692,104.

As noted, the sensors are individually correlated with these masked openings to receive the reflected light from the label and, based upon the amount of light, emit a corresponding signal. By comparing the signals received from the respective areas of indicia 62 and 62', the sensing equipment can determine whether or not the label is in correct position or is askew. Thus, if a label is askew a considerable amount, mask opening 72 might be positioned to include the entire dark area of indicia 62, while mask opening 72' may include only a fraction of dark indicia area 62'. Hence, the light reflected from the latter would be greater than that from the former, and its signal would be comparatively different. The misbalance between them detected by the equipment would indicate that this label was not correctly positioned. (It will be realized that the dark'indicia lessen the amount of light reflected in contrast to the surrounding light label area.) Lateral position of the label may be verified by measurement of the signal from any of the indicia against a standard. Circumferential position of the label will not be detected by the scanning action (normallyabout' .100). It has been found that skew is the most easily noticed labeling appearance defect. About .015" per inch of label width must be measured. This invention makes this measurement practical by providing each photocell with an approximately equal signal which minimizes non-linear responses ofthe photoelectric system.

Therefore, in order to make any of these verification steps reliable, it will be realized that mask areas 72 and 72 and the photoelectric sensors must be oriented directly toward the indicia area. If they are positioned as illustrated in FIG. 5A therefor, a meaningless reading will occur when the sensors are activated. Hence, since the inventor herein has determined that the diameter and hence circumference of typical articles such as pharmaceutical containers vary considerably, the exact position of the leading edge of the label that contains the indicia markings will vary also. Therefore, the photoelectric sensors may or may not be partially or totally aligned with the indicia markings to make an accurate testing.

This novel apparatus uniquely accommodates this variation. Specifically, the verification operation occurs in two stages, the first being a scanning operation to locate the indica markings and align the photoelectric sensors and masking openings with the indicia, and the second step being the true verification step.

This first step of the operation is accomplished by having the photoelectric sensor sub assembly 18 shiftable tiny controlled amounts transversely of the axis of the bottles, i.e. in a plane normal to an imaginary line connecting the position checking indicia 62 and 62, and preferably about a pivotal mounting, so as to cause a slight arcuate movement of sub assembly 18. This is achieved by mounting sub assembly 18 on a pivot axis 78 (FIG. 2), and oscillating sub assembly 18 about this pivot axis through a tiny are by a slow speed synchronous motor 80 connected by crank 82 to the extended lever 84 protruding rearwardly from sub assembly 18. Crank 82 includes an eccentric at the output rotational shaft 80 of motor 80 to axially reciprocate connecting rod 82 and therefore vertically oscillate level 84, to cause sub assembly 18 to oscillate, so that cylinder 62, with its lenses, and the aligned sensors in unit 64 scan a small portion of the label in the indicia area.

In operation, motor 80 is not activated until wheel means 16 positions a bottle in the verification station position. This motor is then activated to cause sub assembly 18 to scan the label area until alignment occurs as explained hereinafter. Subsequently, the sensors are activated to enable the system to test for verification purposes. The activation of motor 80 is achieved through any suitable switch or camming means, each time wheel 16 brings an article to the at rest condition in the verification station. Such cam switch means is illustrated at in schematic FIG. 3. Power is supplied to motor 80 through suitable switch means such as switchable oscillator 92, and through conventional translator means 94 or the like. This sweeping action continues to occur until oscillator 92 is switched by a signal from the signal adder or accumulator 98. The output from accumulator 98 isthe sum of the input from the respective photo cell sensors 102 and 102' corresponding with mask openings 72 and 72 and with indicia markings 62 and 62'. The switch 92 is preset to cause the switching function to occur at a predetermined minimum threshold voltage from the accumulator 98. Hence, viewing FIGS. A and 5B, as the mechanism sweeps toward the indicia markings 62 and 62',the voltage output from both of these change with progressive overlapping and hence orientation of the sensors with the indicia markings. When an alignment condition such as that illustrated in FIG. 5B occurs, the threshold voltage from photo cells 102 and 102' to accumulator 98 and to switch 92 will be sufiicient to switch oscillator 92 and deactivate motor 80-. At this time, this threshold voltage activates comparator circuitry 108 to cause the signals from photo cells sensors 102 and 102 to be compared with each other. If one considerably outbalances the other, an output reject signal will be emitted from comparator 108 to indicate that a particular label is askew and hence not correctly positioned, and therefore not acceptable. Suitable reject equipment (as illustrated for example in the copending application Ser. No. 692,- 104) can then be brought into play to segregate this labeled item from the acceptable remainder.

This entire sequence of operations occurs rapidly, so that, when the article advancing and retaining wheel 16 is again ready to rotate another labeled article, it can do so. When it does, this'entire cycle is repeated.

It is realized that those having ordinary skill in the art, once having studied this disclosure, could conceivably modify the details of the assembly in several different ways to suit a particular installation, type of article, type of label, indicia markings of various types, and the like. Hence the invention is intended to be limited, not specifically to the disclosure made for illustrative purposes, but only by the scope of the appended claims and the reasonable equivalents thereto.

The embodiments of the invention in which an exclusive property or privilege is claimed are defined as follows:

1. Apparatus for determining the verifying labels on articles comprising: article retaining means for positioning, in a predetermined verification position, an article having thereon a label having spaced indicia with difierent light responsive character than the label area surrounding said indicia; electrical photosensitive means, including separate sensing means for the respective indicia, oriented generally toward said indicia; said photosensitive means being shiftable, and motive means to shift it a controlled amount to enable said photosensitive means to scan the indicia bearing portions of the label; scanning control circuitry operably associated with said photosensitive means to activate said motive means for such scanning and to inactivate said motive means when said photosensitive means becomes oriented directly toward the label indicia; and verifying circuitry also operably associated with said photosensitive means to render such responsive to the condition of light sensing of said indicia for verification.

2. The apparatus in claim 1 wherein said verifying circuitry is responsive to the condition of light sensing balance or misbalance between the spaced indicia to detect label misorientation on the article.

3. The apparatus in claim 2 wherein said scanning control circuitry and said accuracy determining circuitry both employ electrical signals from said sensing units.

4. The apparatus in claim 2 wherein said scanning control circuitry sums the signals from both said sensing units and triggers said motive means to become inactive when the summed signals reach a predetermined value.

5. The apparatus in claim 2 wherein said accuracy determining circuitry compares the signals from the sensing units to detect any misbalance therebetween.

6. The apparatus in claim 3 wherein said accuracy determining circuitry compares the signals from the sensing units to detect any misbalance therebetween.

7. The apparatus in claim 1 including article advancing means containing said article retaining means and intermittently shiftable to advance labeled articles successive- 1y to said position.

References Cited UNITED STATES PATENTS 3,029,348 4/ 1962 Heinz 250-222 X 3,140,214 7/1964 Von Hofe 156-354 X 3,378,687 4/1968 Schepler 250-236 X 3,418,456 12/1968 Hamisch et al. 250-219 X WALTER STOLWEIN, Primary Examiner US. Cl. X.R. 156-354; 250-209 

